<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>heart</title>
    <style>
        html {
            background-color: black;
        }
        .span {
            animation: up 2s linear 0s infinite;
        }

        @keyframes up {
            from{
                transform: translateY(0px);
            }
            to{
                transform: translateY(-200px);
            }
        }
    </style>
</head>
<body>
    <script src="./js/heart.js"></script>
</body>
</html>